package com.hunt.framework.util;

import com.hunt.common.support.Convert;
import com.hunt.common.utils.StringUtils;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

/**
 * @program: hunt-lx
 * @description: 客户端工具类
 * @author: Lx
 * @create: 2019-02-01 20:29
 **/
public class ServletUtils
{

    public static final String APP_JSON = "application/json";

    public static final String XML_HTTP_REQUEST = "XMLHttpRequest";
    /**
     * TODO URI是否要换名(觉得不太合适)
     */
    public static final String[] URI = {"json", "xml"};

    private ServletUtils()
    {

    }

    /**
     * 获取String参数
     *
     * @param name 参数名
     * @return
     */
    public static String getParameter(String name)
    {
        return getRequest().getParameter(name);
    }

    /**
     * 获取String参数，并且给定默认值
     *
     * @param name         参数名
     * @param defaultValue 默认值
     * @return
     */
    public static String getParameter(String name, String defaultValue)
    {
        return Convert.toStr(getRequest().getParameter(name), defaultValue);
    }

    /**
     * 获取Integer参数
     *
     * @param name
     * @return
     */
    public static Integer getParameterToInt(String name)
    {
        return Convert.toInt(getRequest().getParameter(name));
    }

    /**
     * 获取Integer参数，并且存在默认值
     *
     * @param name
     * @param defaultValue
     * @return
     */
    public static Integer getParameterToInt(String name, Integer defaultValue)
    {
        return Convert.toInt(getRequest().getParameter(name), defaultValue);
    }


    /**
     * 获取request
     */
    public static HttpServletRequest getRequest()
    {
        return getRequestAttributes().getRequest();
    }

    /**
     * 获取response
     */
    public static HttpServletResponse getResponse()
    {
        return getRequestAttributes().getResponse();
    }

    /**
     * 获取session
     */
    public static HttpSession getSession()
    {
        return getRequest().getSession();
    }

    /**
     * 获取ServletRequestAttributes
     */
    public static ServletRequestAttributes getRequestAttributes()
    {
        RequestAttributes attributes = RequestContextHolder.getRequestAttributes();
        return (ServletRequestAttributes) attributes;
    }

    /**
     * 将字符串渲染到客户端
     *
     * @param response 渲染对象
     * @param string   待渲染的字符串
     * @return null
     */

    public static String renderString(HttpServletResponse response, String string)
    {
        try
        {
            response.setContentType("application/json");
            response.setCharacterEncoding("utf-8");
            response.getWriter().print(string);
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 是否是Ajax异步请求
     *
     * @param request
     */
    public static boolean isAjaxRequest(HttpServletRequest request)
    {
        String accept = request.getHeader("accept");
        if (StringUtils.isNull(accept) && accept.indexOf(APP_JSON) != -1)
        {
            return true;
        }
        String xRequestedWith = request.getHeader("X-Requested-With");
        if (xRequestedWith != null && xRequestedWith.indexOf(XML_HTTP_REQUEST) != -1)
        {
            return true;
        }
        String uri = request.getRequestURI();
        if (StringUtils.inStringIgnoreCase(uri, URI))
        {
            return true;
        }
        String ajax = request.getParameter("__ajax");
        if (StringUtils.inStringIgnoreCase(ajax, URI))
        {
            return true;
        }
        return false;
    }
}
